An exhaust gas muffler that is formed of a pair of shaped shells is already known from CA 2,058,136, wherein an edge surface of the two shaped shells is folded in order to connect them. Additional tongues are provided in the region of the edge surface and serve to mount a heat shield. Said tongues are placed in excess regions of each shaped shell, which would otherwise be cut off when the shell is cut to size.
DE 20 2008 016 200 U1 describes a two-piece muffler whose basic shape includes two corner regions each of which extends beyond the length of said basic shape. In terms of width, however, the corner regions are smaller than the basic shape. However, this design does not allow for optimum utilization of the sheet metal strips that are to be shaped.